Transfer system, transfer method, and transfer apparatus

ABSTRACT

A transfer system includes: a transfer chamber having a side wall provided thereon with a plurality of processing chambers in which a processing is performed on a substrate under a decompressed atmosphere, and configured such that the substrate is transferred in the decompressed atmosphere; a plurality of robots fixed in the transfer chamber and configured to transfer the substrate; and a movable buffer configured to hold the substrate and move in a horizontal direction along the side wall between the side wall and the robots in the transfer chamber. The robots exchange the substrate between the movable buffer and the processing chambers in cooperation with a movement of the movable buffer.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part application of InternationalPatent Application No. PCT/JP2020/004431 filed on Feb. 5, 2020, thedisclosure of which is incorporated herein in its entirety by reference.

TECHNICAL FIELD

The present disclosure relates to a transfer system, a transfer method,and a transfer apparatus.

BACKGROUND

In the related art, a transfer system is known in which a robot with ahand for holding a substrate is disposed inside a transfer chamber whichis brought into a decompressed atmosphere transferring a substrateto/from a processing chamber provided on the side wall of the transferchamber.

For example, a substrate processing apparatus has been proposed in whicha movable robot configured to move in a transfer chamber by being drivenby a linear motor transfers a substrate to/from a plurality ofprocessing chambers provided on the side wall of the transfer chamber(e.g., Japanese Laid-Open Patent Application Publication No.2008-028179).

SUMMARY

According to an aspect of the present disclosure, a transfer systemincludes: a transfer chamber having a side wall provided thereon with aplurality of processing chambers in which a processing is performed on asubstrate under a decompressed atmosphere, and configured such that thesubstrate is transferred under the decompressed atmosphere; a pluralityof robots fixed in the transfer chamber and configured to transfer thesubstrate; and a movable buffer configured to hold the substrate andmove in a horizontal direction along the side wall between the side walland the robots in the transfer chamber. The robots exchange thesubstrate between the movable buffer and the processing chambers incooperation with a movement of the movable buffer.

According to another aspect of the present disclosure, a transfer methodincludes: providing a transfer chamber having a side wall providedthereon with a plurality of processing chambers in which a processing isperformed on a substrate under a decompressed atmosphere, and configuredsuch that the substrate is transferred under the decompressedatmosphere, a plurality of robots fixed in the transfer chamber andconfigured to transfer the substrate, and a movable buffer configured tohold the substrate and move in a horizontal direction along the sidewall between the side wall and the robots in the transfer chamber; andoperating the robots in cooperation with a movement of the movablebuffer, to exchange the substrate between the movable buffer and theprocessing chambers.

According to yet another aspect of the present disclosure, a transferapparatus includes: a plurality of robots fixed in a transfer chamberand configured to transfer a substrate, the transfer chamber having aside wall provided thereon with a plurality of processing chambers inwhich a processing is performed on the substrate under a decompressedatmosphere, and configured such that the substrate is transferred underthe decompressed atmosphere; a movable buffer configured to hold thesubstrate and move in a horizontal direction along the side wall betweenthe side wall and the robots in the transfer chamber; and a controllerconfigured to operate the robots in cooperation with a movement of themovable buffer to exchange the substrate between the movable buffer andthe processing chambers.

The foregoing summary is illustrative only and is not intended to be inany way limiting. In addition to the illustrative aspects, embodiments,and features described above, further aspects, embodiments, and featureswill become apparent by reference to the drawings and the followingdetailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic top view illustrating an outline of a transfersystem according to an embodiment.

FIG. 2A is a schematic top view illustrating an example (part 1) of anarrangement of a load lock chamber.

FIG. 2B is a schematic top view illustrating an example (part 2) of thearrangement of the load lock chamber.

FIG. 3 is a schematic top view illustrating a transfer system accordingto an embodiment.

FIG. 4 is a schematic side view of a robot and a movable buffer.

FIG. 5A is a schematic top view illustrating an example (part 1) of aconfiguration of a robot.

FIG. 5B is a schematic top view illustrating an example (part 2) of aconfiguration of a robot.

FIG. 5C is a schematic top view illustrating an example (part 3) of aconfiguration of a robot.

FIG. 5D is a schematic top view illustrating an example (part 4) of aconfiguration of a robot.

FIG. 5E is a schematic top view illustrating an example (part 5) of aconfiguration of a robot.

FIG. 6 is a schematic top view of a transfer system according to amodification (part 1).

FIG. 7 is a schematic top view of a transfer system according to amodification (part 2).

FIG. 8 is a schematic top view of a transfer system according to amodification (part 3).

FIG. 9 is a schematic top view of a transfer system according to amodification (part 4).

FIG. 10 is a view illustrating a modification of the robot and themovable buffer.

FIG. 11 is a block diagram illustrating a configuration of a transferapparatus.

FIG. 12 is a flowchart illustrating a procedure of a process performedby the transfer apparatus.

FIG. 13A is a perspective view of a multi-stage movable buffer.

FIG. 13B is a perspective view of the movable buffer and a track.

FIG. 14A is a schematic top view of a transfer chamber.

FIG. 14B is a schematic perspective view of the transfer chamber.

FIG. 15 is a view illustrating a modification of the multi-stage movablebuffer.

DETAILED DESCRIPTION

In the following detailed description, reference is made to theaccompanying drawings which form a part hereof. The illustrativeembodiments described in the detailed description, drawings, and claimsare not meant to be limiting. Other embodiments may be utilized, andother changes may be made without departing from the spirit or scope ofthe subject matter presented herein.

In the related art described above, there is a concern that adopting themovable robot may increase costs, or the complicated movement mechanismmay deteriorate the availability. Since the deterioration ofavailability results in the decrease in transfer efficiency of asubstrate, an improvement is necessary from the viewpoint of increasingthe transfer efficiency of an unprocessed substrate and a processedsubstrate.

An aspect of embodiments relates to providing a transfer system, atransfer method, and a transfer apparatus which are capable of improvingthe transfer efficiency of a substrate.

Hereinafter, embodiments of the transfer system, the transfer method,and the transfer apparatus according to the present disclosure will bedescribed in detail with reference to the accompanying drawings. Thepresent disclosure is not limited to the embodiments described hereinbelow.

In the embodiments described herein below, terms such as“perpendicular,” “horizontal,” “vertical,” “parallel,” and “symmetrical”will be used, and these terms do not strictly require to satisfy thestates thereof. That is, the terms allow deviations in, for example,manufacturing accuracy, installation accuracy, process accuracy, anddetection accuracy.

First, the outline of a transfer system 1 according to an embodimentwill be described using FIG. 1. FIG. 1 is a schematic top viewillustrating the outline of the transfer system 1 according to theembodiment. FIG. 1 corresponds to a schematic view of the transfersystem 1 when viewed from above.

In order to facilitate the understanding of descriptions, FIG. 1represents a three-dimensional orthogonal coordinate system in which thevertical upward direction corresponds to the positive direction of the Zaxis, the X axis corresponds to a direction along the side wall 100 swof a transfer chamber 100 with a plurality of processing chambers PCprovided thereon, and the Y axis corresponds to a direction of thenormal lines of the side wall 100 sw. The orthogonal coordinate systemmay also be illustrated in the other drawings to be referred-tothroughout the descriptions. Further, FIG. 1 illustrates a line CL thatcorresponds to the front of a processing chamber PC. The line CLcorresponds to a line (e.g., a line along the Y axis in FIG. 1) thatpasses through the center of a substrate W in the processing chamber PC(see the dashed-line circle), among the normal lines of the side wall100 sw.

As illustrated in FIG. 1, the plurality of processing chambers PC areprovided on the side wall 100 sw outside the transfer chamber 100, toeach perform a processing on the substrate W under a decompressedatmosphere. Here, the processing performed on the substrate W in eachprocessing chamber PC is, for example, a film formation processing suchas a CVD (chemical vapor deposition) or an etching. In general, theenvironment of decompressed atmosphere may be called a “vacuum” state.In the processing chamber PC illustrated in FIG. 1, the double-line sidecorresponds to an opening which is openable/closable.

The transfer chamber 100 has a decompressed atmosphere therein similarto the transfer chamber 100, and a plurality of robots 10 and a movablebuffer 110 are arranged inside the transfer chamber 100 such that boththe robots 10 and the movable buffer 110 transfer the substrate W incooperation with each other. Each robot 10 is a substrate transfermechanism that performs a transfer of the substrate W such as carryingthe substrate W into the processing chamber PC or taking the substrate Wout of the processing chamber PC, and is, for example, a horizontalmulti-joint robot (SCARA robot).

Here, the robot 10 is a “fixed robot” that is fixed to, for example, thefloor 100 f of the transfer chamber 100 (see, e.g., FIG. 4), and isdistinguishable from a “movable robot” that travels or moves in thetransfer chamber 100. Since the robot 10 does not move in the transferchamber 100, power may be easily fed to the robot 10, and thecleanliness of the transfer chamber 100 may be implemented.

The movable buffer 110 temporarily holds the substrate W, and moves in ahorizontal direction D along the side wall 100 sw between the side wall100 sw and the robots 10. For example, the movable buffer 110 is drivenin a non-contact manner by a linear motor or the like. FIG. 1illustrates a movement path ML of the movable buffer 110 for reference.Here, since the side wall 100 sw illustrated in FIG. 1 is linear in thetop view, the horizontal direction D1 or the movement path ML is linear.However, when the side wall 100 sw is curved in the top view, thehorizontal direction D1 or the movement path ML may also be curved alongthe side wall 100 sw.

The robot 10 performs the exchange of the substrate W between themovable buffer 110 and the processing chamber PC in cooperation with themovement of the movable buffer 110. Specifically, in a case where therobot 10 carries the substrate W into the processing chamber PC, themovable buffer 110 that is holding an unprocessed substrate W moves tothe vicinity of the robot 10. The robot 10 acquires the unprocessedsubstrate W from the movable buffer 110, and carries the acquiredunprocessed substrate W into the processing chamber PC.

Further, in a case where the robot 10 takes the substrate W out of theprocessing chamber PC, the movable buffer 110 in an empty state (whichis holding no substrate W) moves to the vicinity of the robot 10. Therobot 10 takes the processed substrate W out of the processing chamberPC, and delivers the taken processed substrate W to the movable buffer110.

As illustrated in FIG. 1, when the plurality of robots 10 are arrangedin front of the processing chambers PC, respectively, the movable buffer110 may also stop in front of each processing chamber PC (e.g., themovable buffer 110 indicated in the dashed line in FIG. 1). As a result,the moving distance of the substrate W may be minimized when the robot10 takes the substrate W into/out of the processing chamber PC, so thatthe transfer efficiency may be improved. Further, since the operation ofthe robot 10 may be simplified, the configuration of the robot 10 mayalso be simplified, so that costs may be reduced.

In this way, when the movable buffer 110 is adopted as a buffer, theweight of the moving subject may be reduced, as compared with a casewhere a movable robot is adopted as the robot 10, so that the movingmechanism may be simplified. As a result, the operation rate of themoving mechanism is improved, and the availability for the transfer ofthe substrate W may increase, so that the transfer efficiency of thesubstrate W may be improved.

In recent years, there has been a tendency that the processing time forthe substrate W in each processing chamber PC increases due to, forexample, the multi-layering of semiconductors formed on the substrate W.Accordingly, there is a demand for increasing the number of processingchambers PC per transfer chamber 100, so as to improve the number ofsubstrates to be processed per unit time.

The demand may be satisfied by improving the transfer efficiency of thesubstrate W in the transfer chamber 100, as in the transfer system 1.Further, by adopting a fixed robot as the robot 10, the height of thetransfer chamber 100 may be reduced, thereby reducing the volume of thetransfer chamber 100. As a result, the operation costs of the transferchamber 100 may be reduced.

While FIG. 1 illustrates only a portion of the transfer chamber 100, anexample of the arrangement of the processing chambers PC, the robots 10,the movable buffer 110 and others in the entire transfer chamber 100will be described later using, for example, FIG. 3. Further, an exampleof the configuration of each robot 10 and the movable buffer 110 will bedescribed later using, for example, FIG. 4.

While the robot 10 illustrated in FIG. 1 is also able to access a loadlock chamber that corresponds to the entrance/exit of the substrate W inthe transfer chamber 100, variations may be made to the shape of the topsurface of the transfer chamber 100 and the arrangement of the load lockchamber and the processing chambers PC.

Thus, hereinafter, an example of the arrangement of the load lockchamber will be described using FIGS. 2A and 2B. For a load lock chamberprovided with a robot therein, when the robot is able to transfer thesubstrate W to/from the movable buffer 110, the robot 10 illustrated inFIG. 1 is not required to have the ability to access the load lockchamber. Further, as illustrated in FIG. 1, the apparatus that includesthe robots 10 and the movable buffer 110 may be referred to as atransfer apparatus 5.

FIGS. 2A and 2B are schematic top views illustrating examples (parts 1and 2) of the arrangement of the load lock chamber LL. FIGS. 2A and 2Bomit the illustration of the robots 10 and the movable buffer 110illustrated in FIG. 1. Further, FIGS. 2A and 2B represent a case wherethe transfer chamber 100 has a rectangular shape in the top view, andthe processing chambers PC are provided on the relatively long sides ofthe rectangular shape. When the processing chambers PC are arranged onthe relatively long sides of the rectangular transfer chamber 100, thetransfer chamber 100 may be flexibly expanded even in a case where thenumber of processing chambers PC increases.

Further, FIGS. 2A and 2B represent the side walls 100 sw that correspondto the relatively long sides of the rectangle (see, e.g., FIG. 1) as theside walls 100 sw 1 and 100 sw 2, respectively, and represent the sidewalls 100 sw that correspond to the relatively short sides of therectangle as the side walls 100 sw 3 and 100 sw 4, respectively.Further, FIGS. 2A and 2B represent the plurality of processing chambersPC (e.g., an “n” number of processing chambers PC) as processingchambers PC1 to PCn.

FIG. 2A represents a case where the load lock chamber LL is provided onthe side wall 100 sw 1 on which the plurality of processing chambers PCare provided. Here, the load lock chamber LL changes its internalpressure between the decompressed atmosphere and theatmospheric-pressure atmosphere. For example, when the substrate W (see,e.g., FIG. 1) is carried into the transfer chamber 100 from the outside,the internal pressure of the load lock chamber LL is adjusted to theatmospheric-pressure atmosphere, and a first port that is an outwardopening of the load lock chamber LL is opened. After the first port isclosed, the internal pressure of the load lock chamber LL is adjusted tothe decompressed atmosphere, and a second port that is an opening of theload lock chamber LL toward the transport chamber 100 is opened.

FIG. 2B represents a case where the load lock chamber LL is provided onthe side wall 100 sw 3 (e.g., the relatively short side) adjacent to theside wall 100 sw 1 (e.g., the relatively long side) on which theplurality of processing chambers PC are provided. In this way, the loadlock chamber LL may be disposed on the side wall 100 sw different fromthe side wall 100 sw on which the processing chambers PC are provided.While FIG. 2B represents a case where the load lock chamber LL isprovided on the side wall 100 sw 3, the load lock chamber LL may beprovided on the side wall 100 sw 4.

Further, while FIGS. 2A and 2B represent a case where the transferchamber 100 has a rectangular shape in the top view, the transfer system1 illustrated in FIG. 1 may well be applied even when the transferchamber 10 has other shapes such as a polygonal or circular shape.Hereinafter, the configuration of the transfer system 1 will bedescribed in more detail.

FIG. 3 is a schematic top view of the transfer system 1 according to theembodiment. As illustrated in FIG. 3, four processing chambers PC areprovided at each side of the opposite positions of the side walls 100 sw1 and 100 sw 2 which are parallel to each other. Further, each robot 10is disposed at an intermediate position between the processing chambersPC of which openings face each other, in front of the openings of theprocessing chambers PC.

Specifically, a total number of four robots 10 are arranged such thatone is disposed in front of the processing chambers PC1 and PC5, anotherone is disposed in front of the processing chambers PC2 and PC6, yetanother one is disposed in front of the processing chambers PC3 and PC7,and the other one is disposed in front of the processing chambers PC4and PC8.

The load lock chambers LL are arranged on the side wall 100 sw which isnot parallel to the side walls 100 sw 1 and 100 sw 2, and are accessiblefrom the robot 10 disposed closest to the load lock chambers LL (see,e.g., the load lock chambers LL1 and LL2).

That is, at least one of the plurality of robots 10 exchanges thesubstrate W (see, e.g., FIG. 1) between the movable buffer 110 and aprocessing chamber PC or a load lock chamber LL. In this way, when therobot 10 in the transfer chamber 100 accesses the load lock chambers LLas well, it is unnecessary to provide a robot in each load lock chamberLL, so that the load lock chambers LL may be downsized.

As illustrated in FIG. 3, the transfer chamber 100 is symmetric withrespect to the “line of symmetry” parallel to the side walls 100 sw 1and 100 sw 2. Thus, hereinafter, the configuration of the transferchamber 100 close to the side wall 100 sw 1 (e.g., on the side of thepositive direction of the Y axis) will be mainly described.

As illustrated in FIG. 3, the side wall 100 sw 1 is linear in the topview, and the plurality of processing chambers PC (e.g., PC1 to PC4) arearranged in the horizontal direction on the side wall 100 sw 1. Therobots 10 are provided along the arrangement direction of the processingchambers PC. The movable buffer 110 moves along a track 120 fixed to,for example, the floor surface of the transfer chamber 100. The movablebuffer 110 and the track 120 may be collectively referred to as themovable buffer 110. The configuration of the movable buffer 110 and thetrack 120 will be described later using FIG. 4.

The track 120 includes a linear track 121 that has a straight-lineshape. In this way, when the movable buffer 110 moves along the lineartrack 121, the position accuracy of the movable buffer 110 may beimproved. While FIG. 3 illustrates two linear tracks 121 because theprocessing chambers PC are provided on both the side walls 100 sw thatface each other, the number of linear tracks 121 may be one.

At least one of the plurality of linear tracks 121 may be so-called“double tracks.” In this case, the double tracks may have a heightdifference in order to prevent the movable buffers 110 moving on thedouble tracks, respectively, from interfering with each other. Further,the “double tracks” may be provided by arranging the linear tracks 121having different heights to be adjacent to each other.

The track 120 may include a curved portion 122 that is curved in adirection away from the side wall 100 sw, at at least one of both theends of the linear track 121. When the curved portion 122 is provided atone end of the linear track 121, the curved portion 122 may be used as aretreating place of the movable buffer 110 or a reset place forresetting the position of the movable buffer 110. As a result, theavailability of the movable buffer 110 may be improved. Further, thecurved portion 122 may branch from the middle of the linear track 121.

FIG. 3 illustrates the track 120 provided with the curved portion 122 ateach end of the linear track 121. In the following descriptions, forexample, in a case where the curved portion 122 connects the two lineartrackes 121 to each other, the “curved portion 122” may be referred toas a “curved track 122.”

As illustrated in FIG. 3, the transfer chamber 100 includes the lineartrack 121 provided between the side wall 100 sw 1 and the robots 10, andthe linear track 121 provided between the side wall 100 sw 2 and therobots 10. Further, at least one movable buffer 110 moves along eachlinear track 121. In this way, when the linear tracks 121 are providedin parallel to each other while interposing the robots 10 therebetween,each robot 10 may use the movable buffer 110 that moves on the lineartrack 121 relatively close to a processing chamber PC, so that themoving distance of the substrate W may be reduced when the substrate Wis transferred. Accordingly, the transfer efficiency of the substrate Wmay be improved.

Here, the movable buffer 110 illustrated in FIG. 3 includes holdingmodules 111 that hold the substrate W, and a connection module 115. Theholding modules 111 are connected to both the ends of the connectionmodule 115 in the horizontal direction via joints J that allow ahorizontal rotation.

In this way, the holding modules 111 may be connected to both the endsof the connection module 115. As a result, even when the moving range ofthe connection module 115 is limited to the linear track 121, theholding modules 111 may move to the curved portions 122 provided at theends of the linear track 121. When it is sufficient that the movablebuffer 110 moves on the linear track 121, a non-rotatable type of jointJ may be provided, or the joint J itself may be omitted such that theholding modules 111 and the connection module 115 may be fixed to andintegrated with each other.

For example, the movable buffer 110 may move the holding module 111 tothe front of the load lock chamber LL1 along the curved portion 122, ina state where the connection module 115 is disposed on the linear track121. Further, the movable buffer 110 may move any one of the connectedholding modules 111 to the front of a processing chamber PC (e.g., PC1to PC4).

As illustrated in FIG. 3, a pair of substrate detection sensors S isprovided in the opening of each processing chamber PC, and may detect atleast two points on the outer periphery of the substrate W, so as tocalculate the central position of the substrate W transferred to theprocessing chamber PC. As a result, the positional deviation between thesubstrate W and the robot 10 that transfers the substrate W may bedetected, and the operation of the robot 10 may be corrected so that thesubstrate W may be moved to a regular position in the processing chamberPC. Further, the substrate detection sensors S may be provided on thefloor surface or the ceiling surface of the transfer chamber 100.

Among the plurality of robots 10, the robot 10 closest to the load lockchambers LL is able to access the load lock chambers LL1 and LL2, andthe processing chambers PC1 and PC5. The other robots 10 are able toaccess their facing processing chambers PC (e.g., the processingchambers PC2 and PC6, the processing chambers PC3 and PC7, and theprocessing chambers PC4 and PC8), respectively. As described above, theholding module 111 of the movable buffer 110 may move to the front ofeach processing chamber PC (PC1 to PC8).

Next, an example of the configuration of the robot 10 and the movablebuffer 110 will be described using FIG. 4. FIG. 4 is a schematic sideview of the robot 10 and the movable buffer 110. Further, FIG. 4represents a schematic side view of the robot 10 and the movable buffer110 illustrated in FIG. 1 when viewed from the positive direction of theX axis.

First, an example of the configuration of the robot 10 will bedescribed. As illustrated in FIG. 4, the robot 10 includes a first arm11, a second arm 12, a hand 13, a lifting mechanism 15, a flange F, anda base B.

The base B of the robot 10 penetrates the floor 100 f of the transferchamber 100, and projects outside the transfer chamber 100. The flange Fsupports the robot 10 on the upper surface of the floor 100 f, andmaintains the airtightness of the transfer chamber 100. In this way,when the base B of the robot 10 projects from the transfer chamber 100,the volume of the transfer chamber 100 may be reduced. Further, feedingpower to the robot 10 from the outside of the transfer chamber 100 oraccessing the robot 10 may be readily performed.

The lifting mechanism 15 supports the base end of the first arm 11 to berotatable around a first rotation axis AH1, and moves up and down alonga lifting axis AV. The lifting mechanism 15 itself may be rotated aroundthe first rotation axis AH1. The first arm 11 supports the base end ofthe second arm 12 at the tip end thereof, to be rotatable around asecond rotation axis AH2. The second arm 12 supports the base end of thehand 13 at the tip end thereof, to be rotatable around a third rotationaxis AH3. For example, as illustrated in FIG. 1 or 3, the hand 13includes a fork portion formed such that the tip end of the hand 13 isbifurcated, and supports the substrate W on the upper surface thereof.The hand 13 may hold a plurality of substrates W in multiple stages.

Here, the first arm 11, the second arm 12, and the hand 13 thatcorrespond to horizontal arms may pivot independently of each otheraround the first rotation axis AH1, the second rotation axis AH2, andthe third rotation axis AH3, respectively. Further, the second arm 12and the hand 13 may pivot by being driven by the pivoting of the firstarm 11 around the first rotation axis AH1.

When the first arm 11, the second arm 12, and the hand 13 pivotindependently from each other, three driving sources (e.g., actuators)are required, and when the second arm 12 and the hand 13 pivot by beingdriven by the pivoting of the first arm 11, one or two driving sourcesare required. Further, the robot 10 requires another driving source formoving the lifting mechanism 15 up and down. Here, variations may bemade to the configuration of the axes of the robot 10, and detailsthereof will be described later using FIGS. 5A to 5D.

Next, an example of the configuration of the movable buffer 110 will bedescribed. The movable buffer 110 includes the holding module 111 thatholds the substrate W, and a driving module 112. Here, the drivingmodule 112 illustrated in FIG. 4 corresponds to a mover of amoving-magnet type linear motor. Thus, in the following descriptions,the “driving module 112” may be referred to as a “mover 112.” Here, thetype of linear motor is not limited to the moving-magnet type, and maybe an induction (e.g., dielectric) type. In the present embodiment, acase where the moving-magnet type linear motor, that is, the mover 112includes a permanent magnet will be described. However, the mover 112may be formed of a material that moves by the flow of a dielectriccurrent.

Further, the track 120 includes a stator 120 a that corresponds to astator of the linear motor, and a guide 120 b. In the presentembodiment, a case where the movable buffer 110 moves on the track 120by the driving force of the linear motor will be described. However, themovable buffer 110 may be a contact type, or a non-contact type such asa magnetic levitation type or an air levitation type. The guide 120 b isa support member that guides a linear or curved movement in a plane suchas a horizontal plane. In the case illustrated in FIG. 4, the guide 120b guides the linear movement of the movable buffer 110 in the directionalong the X axis.

In this way, the driving module 112 of the movable buffer 110 is drivenin a non-contact manner by the stator 120 a included in the track 120.For example, the stator 120 a is formed by molding a winding with aresin or the like, and covering the surface of the mold with a film-likemetal. This metal film is also called a can, and traps a gas generatedfrom the resin or the like inside. In this way, the movable buffer 110is driven in a moving-magnet type non-contact manner, which contributesto the cleanliness of the transfer chamber 100. Further, power may befed to the stator 120 a through the floor 100 f of the transfer chamber100, which also contributes to the cleanliness of the transfer chamber100.

As illustrated in FIG. 4, when the movable buffer 110 holds thesubstrate W, the robot 10 moves the hand 13 up, so as to receive thesubstrate W as if to lift up the substrate W. In contrast, when the hand13 holds the substrate W, the robot 10 moves the hand 13 down, so as todeliver the substrate W to the movable buffer 110.

The position of the holding module 111 in the top view may be acquiredbased on a variation in current or voltage of the stator 120 a of thetrack 120 or a detection result of a position sensor appropriatelyprovided on the guide 120 b.

Next, an example of the configuration of the robot 10 will be describedusing FIGS. 5A to 5D. FIGS. 5A to 5D are schematic top viewsillustrating examples (parts 1 to 4) of the configuration of the robot10.

The robot 10 illustrated in FIG. 5A is a first robot 10A with threedegrees of freedom which include one degree of freedom in the verticaldirection and two degrees of freedom in the horizontal direction. WhileFIG. 5A represents a lifting axis AV and a first rotation axis AH1 to becoaxial, the axes may not be coaxial. The first arm 11, the second arm12, and the hand 13 which are horizontal arms operate in cooperationwith each other, such that the substrate center CW moves in the radialdirection of the first rotation axis AH1 while maintaining the postureof the hand 13.

That is, the second arm 12 is driven to pivot around the second rotationaxis AH2, and the hand 13 is driven to pivot around the third rotationaxis AH3, by the driving force for pivoting the first arm 11 around thefirst rotation axis AH1, and a transmission mechanism. As thetransmission mechanism, for example, a belt, a gear, or a link mechanismmay be used. The “substrate center CW” indicates the central position ofthe substrate W when the hand 13 holds the substrate W at a regularposition.

In this way, the first robot 10A changes the distance “r” from the firstrotation axis AH1 to the substrate center CW, while constantlymaintaining the angle θ of the straight line that passes through thefirst rotation axis AH1, the third rotation axis AH3, and the substratecenter CW. Here, the angle θ may be any angle. As described above, thefirst robot 10A is the robot 10 with three degrees of freedom whichinclude one degree of freedom in the vertical direction and two degreesof freedom in the horizontal direction. In the following descriptions,the first robot 10A may be referred to as an “RθZ robot.”

When the first robot 10A that is the RθZ robot is used as the robot 10,costs for the robot 10 may be reduced, as compared with a case where therobot 10 has four or more degrees of freedom. Further, when the firstrobot 10A is used as the robot 10, the first robot 10A is disposed infront of the processing chamber PC or the load lock chamber LL. In otherwords, when the robot 10 is disposed in front of the processing chamberPC or the load lock chamber LL, the RθZ robot with three degrees offreedom may be used as the robot 10.

The robot 10 illustrated in FIG. 5B is a second robot 10B with four ormore degrees of freedom which include one degree of freedom in thevertical direction and three or more degrees of freedom in thehorizontal direction. While FIG. 5B represents the lifting axis AV andthe first rotation axis AH1 to be coaxial, the axes may not be coaxial.Unlike the first robot 10A illustrated in FIG. 5A, the first arm 11, thesecond arm 12, and the hand 13 that are horizontal arms pivotindependently from each other around the first rotation axis AH1, thesecond rotation axis AH2, and the third rotation axis AH3, respectively.

In this way, since the second robot 10B has at least one redundant axisin the horizontal direction, the second robot 10B may move the substratecenter CW in any path. Thus, when the second robot 10B is used as therobot 10, the second robot 10B is not required to be disposed in frontof the processing chamber PC or the load lock chamber LL. In otherwords, the robot 10 may deliver the substrate W to/from the processingchamber PC or the load lock chamber LL, even though the robot 10 is notdisposed in front of the processing chamber PC or the load lock chamberLL.

The robot 10 illustrated in FIG. 5C is a third robot 10C in which thehorizontal arm of the first robot 10A illustrated in FIG. 5A is used asa dual arm (both arms). That is, the third robot 10C includes a dual armthat each has two degrees of freedom in the horizontal direction, andone degree of freedom in the vertical direction. Specifically, the baseends of the two first arms 11 are supported by a pedestal P, and thepedestal P moves up and down along the lifting axis AV and rotatesaround a rotation axis AH0. While FIG. 5C represents a case where thedual arm includes the horizontal arm of the first robot 10A illustratedin FIG. 5A, the dual arm may include the horizontal arm of the secondrobot 10B illustrated in FIG. 5B. Further, the rotation axis AH0 may beomitted.

The third robot 10C illustrated in FIG. 5D is a modification of thethird robot 10C illustrated in FIG. 5C. The third robot 10C illustratedin FIG. 5D is different from the third robot 10C illustrated in FIG. 5Cin that the lifting axis AH0 and the two first rotation axes AH1 of thedual arm are coaxial. With the configuration, the compact size of thethird robot 10C may be implemented, so that the volume of the transferchamber 100 may be reduced. Further, the vertical relationship of thearms in the dual arm illustrated in FIG. 5D may be reversed. Further,the rotation axis AH0 may be omitted for the same reason as that for thethird robot 10C illustrated in FIG. 5C.

The robot 10 illustrated in FIG. 5E is a robot 10D with two degrees offreedom which include one degree of freedom in the vertical directionand one degree of freedom in the horizontal direction. The robot 10Dincludes a slider 16 and a double-fork hand 17. The slider 16 supportsthe double-fork hand 17 in which two fork portions configured to eachhold the substrate W are connected back to back, to be movable in thehorizontal direction.

Since the robot 10D does not have a rotation axis around the verticalaxis, the direction of the double-fork hand 17 may not be changed. Thus,the robot 10D is disposed at a position in front of the processingchambers PC that face each other, on the extension line of the slidingdirection of the double-fork hand 17 (e.g., in the Y-axis direction inFIG. 5E).

Next, a modification of the transfer system 1 illustrated in FIG. 3 willbe described using FIGS. 6 to 9. FIGS. 6 to 9 are schematic top views ofthe transfer system 1 according to modifications (parts 1 to 4). In thefollowing descriptions, differences from the transfer system 1illustrated in FIG. 3 will be mainly described, and overlappingdescriptions will be appropriately omitted.

The transfer system 1 illustrated in FIG. 6 is different from thetransfer system 1 illustrated in FIG. 3 in that the shape of the track120 is so-called a “U-shape.” Specifically, in the track 120, one-sideends of the pair of linear tracks 121 are connected to each other toform the curved track 122 (the curved portion 122). Accordingly, eachmovable buffer 110 may move from one linear track 121 to the otherlinear track 121 via the curved track 122.

Further, the transfer system 1 illustrated in FIG. 6 is different fromthe transfer system 1 illustrated in FIG. 3 in that the movable buffers110 are not connected to each other. Accordingly, each movable buffer110 may move independently along the track 120. While FIG. 6 representsthree movable buffers 110, one or any number of movable buffers 110 maybe provided.

FIG. 6 represents a case where the first robot 10A (the RθZ robot)illustrated in FIG. 5A is disposed as the robot 10 (see, e.g., FIG. 3).Further, the positional relationship between the processing chambersPC/the load lock chambers LL and each first robot 10A is similar to thatfor the robot 10 illustrated in FIG. 3. Meanwhile, the robot 10illustrated in FIG. 3 may be appropriately selected from the firstrobots 10A to 10D illustrated in FIGS. 5A to 5D, respectively, accordingto the positional relationship with the processing chambers PC/the loadlock chambers LL.

The transfer system 1 illustrated in FIG. 7 is different from thetransfer system 1 illustrated in FIG. 3 in that the track 120 hasso-called an “annular” shape, and the movable buffers 110 are notconnected to each other. Specifically, in the track 120, the one-sideends of the pair of linear tracks 121 are connected to each other, andthe other-side ends of the pair of linear tracks 121 are connected toeach other, so as to form the curved tracks 122 (e.g., the curvedportions 122), respectively. Accordingly, each movable buffer 110 maycirculate independently on the annular track 120. While FIG. 7represents four movable buffers 110, one or any number of movablebuffers 110 may be provided, as in the transfer system 1 illustrated inFIG. 6.

FIG. 7 represents a case where the first robot 10A (e.g., the RθZ robot)illustrated in FIG. 5A is disposed as the robot 10 closest to the loadlock chambers LL, and the robot 10D illustrated in FIG. 5D is disposedas each of the other robots 10.

The first robot 10A is able to access each of the two load lock chambersLL and the two processing chambers PC that face each other. Each robot10D is able to access the two processing chambers PC that face eachother. Instead of the robot 10D, the first robot 10A or the second robot10B may be used.

The transfer system 1 illustrated in FIG. 8 is different from thetransfer system 1 illustrated in FIG. 3 in that the track 120 hasso-called an “annular” shape,” and the movable buffers 110 are connectedto each other along the annular track 120. Specifically, the movablebuffers 110 include a plurality of connection modules 115 between theholding modules 111, and are connected to each other via joints J thatallow a horizontal rotation, so as to form the annular shape.

The annular movable buffers 110 move (circulate) along the annular track120, so that any one holding module 111 may move to the front of any oneprocessing chamber PC or any one load lock chamber LL. While FIG. 8represents five holding modules 111, one or any number of holdingmodules 111 may be provided. Further, while FIG. 8 represents threeconnection modules 115 between the holding modules 111, one or anynumber of connection modules 115 may be provided as long as the movablebuffers 110 are connected in the annular shape.

While FIG. 8 represents the movable buffers 110 connected in the annularshape, a plurality of movable buffers 110 connected in a non-annularshape may be provided. In this case, each movable buffer 110 may moveindependently. Further, each of the robots 10 (see, e.g., FIG. 3) is thefirst robot 10A, as in the transfer system 1 illustrated in FIG. 6.

The transfer system 1 illustrated in FIG. 9 is different from thetransfer system 1 illustrated in FIG. 3 in that the track 120 hasso-called an “annular” shape, the movable buffers 110 are not connectedto each other, and the number of robots 10 (see, e.g., FIG. 3) is small.Since the transfer system 1 illustrated in FIG. 9 is identical to thetransfer system 1 illustrated in FIG. 7 in that the track 120 hasso-called an “annular” shape, and the movable buffers 110 are notconnected to each other, the reduced number of robots 10 will bedescribed below.

Specifically, the robots 10 are the first robot 10A illustrated in FIG.5A, the second robot 10B illustrated in FIG. 5B, and the robot 10Dillustrated in FIG. 5D from the robot relatively closer to the load lockchambers LL. Here, the first robot 10A is able to access the load lockchambers LL1 and LL2, and the processing chambers PC1 and PC5. Thesecond robot 10B is able to access the processing chambers PC2, PC3,PC6, and PC7. The robot 10D is able to access the processing chambersPC4 and PC8.

In this way, when the second robot 10B with four or more degrees offreedom which include one degree of freedom in the vertical directionand three or more degrees of freedom in the horizontal direction is usedas the robot 10, the number of accessible processing chambers PCincreases, so that the number of robots 10 may be reduced. Further,instead of the first robot 10A or the robot 10D illustrated in FIG. 9,the second robot 10B may be used.

Instead of the first robot 10A illustrated in FIG. 9, the third robot10C which is a dual-arm robot may be used. In this way, when the thirdrobot 10C which is a dual-arm robot is used as the robot 10 thataccesses the load lock chambers LL, it is possible to make a quickaccess to the load lock chambers LL which tend to become a bottleneck ofthe transfer process, so that the transfer efficiency of the substrate Wmay be improved.

Next, a modification of the robot 10 and the movable buffer 110illustrated in FIG. 4 will be described using FIG. 10. FIG. 10 is a viewillustrating a modification of the robot 10 and the movable buffer 110.Further, FIG. 10 represents a schematic side view similar to FIG. 4.Here, the robot 10 and the movable buffer 110 illustrated in FIG. 10 aredifferent from those in FIG. 4 in that the robot 10 is a fourth robot10E that does not include the lifting mechanism, and instead, themovable buffer 110 is a movable buffer 110A that includes the liftingmechanism. Thus, hereinafter, the differences from FIG. 4 will be mainlydescribed.

As illustrated in FIG. 10, since the fourth robot 10E omits the liftingaxis AV and the lifting mechanism 15 from the robot 10 illustrated inFIG. 4, the fourth robot 10E has two degrees of freedom in thehorizontal direction. Further, since the lifting axis AV and the liftingmechanism 15 are omitted, the height of the base B is suppressed to belower than that of the robot 10 illustrated in FIG. 4. Meanwhile, themovable buffer 110A includes a lift-type holding module 111 s that movesup and down along a vertical lift axis AL.

In this way, when the lifting mechanism is omitted from the robot 10,the height of the transfer chamber 100 may be lowered. Further, theconfiguration of the robot 10 is simplified, so that the availability ofthe robot 10 may be improved.

Meanwhile, DC power is fed to a driving source (e.g., actuator) fordriving the lift-type holding module 111 s in a non-contact mannerthrough the track 120. In this way, when power is fed to the movablebuffer 110A in the non-contact manner, sensors such as a weight sensoror an optical sensor, and devices such as a wireless-communicationcamera may be mounted on the movable buffer 110A.

Accordingly, the presence/absence, shape, weight, position and others ofthe substrate W may be detected while the substrate W is placed on themovable buffer 110A. Further, since costs for feeding the DC power arelower than those for feeding AC power, the supply of DC powercontributes to the reduction in costs.

As illustrated in FIG. 10, when the movable buffer 110A holds thesubstrate W, the movable buffer 110A moves the lift-type holding module111 s down so as to deliver the substrate W to the hand 13 of the fourthrobot 10E. On the contrary, when the hand 13 of the fourth robot 10Eholds the substrate W, the movable buffer 110A moves the lift-typeholding module 111 s upward from below so as to receive the substrate Was if to lift up the substrate W.

The first robot 10A illustrated in FIG. 5A, the second robot 10Billustrated in FIG. 5B, the third robot 10C illustrated in FIG. 5C, andthe fourth robot 10E illustrated in FIG. 10 may be simply referred to asthe robots 10. When the movable buffer 110A provided with the lift-typeholding module 111 s is used as illustrated in FIG. 10, the liftingmechanism 15 (see, e.g., FIG. 4) may be omitted from the robots 10illustrated in FIGS. 1 to 9.

Next, the configuration of the transfer apparatus 5 illustrated in FIG.1 will be described using FIG. 11. FIG. 11 is a block diagramillustrating the configuration of the transfer apparatus 5. Asillustrated in FIG. 11, the transfer apparatus 5 includes the robot 10,the movable buffer 110, and a controller 20. The robot 10 and themovable buffer 110 are connected to the controller 20. The load lockchamber LL and the processing chamber PC are also connected to thecontroller 20, so that the transmission of information is possible.

The controller 20 includes a control unit 21 and a storage unit 22. Thecontrol unit 21 includes an acquisition unit 21 a and an operationcontrol unit 21 b. The storage unit 22 stores teaching information 22 a.While FIG. 11 illustrates one controller 20 for the simplification ofdescriptions, a plurality of controllers 20 may be used. In this case, ahigher-level controller may be provided to bind the other controllers.For example, a controller to which the robot 10 is connected and acontroller to which the movable buffer 110 is connected may be providedas separate controllers, and a higher-level controller may be providedto bind the controllers.

Here, the controller 20 includes, for example, a computer provided witha CPU (central processing unit), a ROM (read only memory), a RAM (randomaccess memory), an HDD (hard disk drive), an input/output port andothers, or various circuits. The CPU of the computer reads and executesprograms stored in, for example, the ROM, so as to function as theacquisition unit 21 a and the operation control unit 21 b of the controlunit 21.

Further, at least one or all of the acquisition unit 21 a and theoperation control unit 21 b may be configured by hardware such as anASIC (application specific integrated circuit) or an FPGA (fieldprogrammable gate array).

The storage unit 22 corresponds to, for example, a RAM or an HDD. TheRAM or HDD may store the teaching information 22 a. The controller 20may acquire the programs described above or various types of informationthrough another computer or a portable record medium connected via awired or wireless network. As described above, the controller 20 may beconfigured by a plurality of devices capable of communicating with eachother, or hierarchical devices capable of communicating with a higher-or lower-level device.

The control unit 21 acquires trigger information such as an accessrequest from the load lock chamber LL or the processing chamber PC, andcontrols the operations of the robot 10 and the movable buffer 110. Whena plurality of controllers 20 is provided, the control unit 21 may alsoperform a synchronization of the plurality of controllers 20.

The acquisition unit 21 a acquires the trigger information such as anaccess request from the load lock chamber LL or the processing chamberPC. Then, the acquisition unit 21 a determines an operation timing oroperation contents of the robot 10 and the movable buffer 110 based onthe acquired information, and notifies the operation control unit 21 bof the determined operation timing or operation contents.

For example, the acquisition unit 21 a acquires a timing when thesubstrate W is carried into the load lock chamber LL from the outside,and instructs the operation control unit 21 b to operate the robot 10and the movable buffer 110 in cooperation with each other based on theacquired timing. Further, the acquisition unit 21 a acquires a timingwhen a processing on the substrate W is completed, from the processingchamber PC, and instructs the operation control unit 21 b to operate therobot 10 and the movable buffer 110 in cooperation with each other basedon the acquired timing.

The operation control unit 21 b operates the robot 10 and the movablebuffer 110 based on the instruction from the acquisition unit 21 a andthe teaching information 22 a. Further, the operation control unit 21 bimproves the operation accuracy of the robot 10 and the movable buffer110 by, for example, performing a feedback control using encoder valuesin actuators such as rotary motors or linear motors which are the powersources of the robot 10 and the movable buffer 110.

The teaching information 22 a is generated at a teaching stage forteaching an operation to the robot 10 and the movable buffer 110, andincludes a “job” which is a program that defines an operation path of arobot or the like. When the robots are arranged at regular positionssuch as line-symmetric positions as illustrated in, for example, FIG. 3,the teaching data may be shared or used inversely. Thus, according tothe transfer apparatus 5, it is possible to reduce the time and costsfor generating the teaching information 22 a that includes the teachingdata.

Next, an example of the procedure of the process performed by thetransfer apparatus 5 illustrated in FIG. 1 will be described using FIG.12. FIG. 12 is a flowchart illustrating the procedure of the processperformed by the transfer apparatus 5. As illustrated in FIG. 12, whenthe acquisition unit 21 a of the controller 20 acquires a notificationof a storage of the substrate W in the load lock chamber LL (step S101),the movable buffer 110 of which operation is controlled by the operationcontrol unit 21 b of the controller 20 moves to the front of the loadlock chamber LL (step S102).

Then, the robot 10 of which operation is controlled by the operationcontrol unit 21 b of the controller 20 transfers the substrate W fromthe load lock chamber LL to the movable buffer 110 (step S103).Subsequently, the mobile buffer 110 to which the substrate W has beentransferred moves to the front of the processing chamber PC (step S104),and the robot 10 transfers the substrate W from the movable buffer 110to the processing chamber PC (step S105).

Further, when the acquisition unit 21 a of the controller 20 acquires anotification of the completion of a processing on the substrate W in theprocessing chamber PC (step S106), the movable buffer 110 moves to thefront of the processing chamber PC (step S107). Subsequently, the robot10 transfers the substrate W from the processing chamber PC to themovable buffer 110 (step S108).

Then, the movable buffer 110 to which the substrate W has beentransferred moves to the front of the load lock chamber LL (step S109),the robot 10 transfers the substrate W from the movable buffer 110 tothe load lock chamber LL (step S110), and the process ends.

While FIG. 12 represents a case where the processes triggered by theacquiring processes in steps S101 and S106, respectively, are performedin series in order to facilitate the understanding of descriptions, theprocesses triggered by the acquiring processes may be performed inparallel. For example, the exchange of the substrate W with respect tothe load lock chamber LL and the exchange of the substrate W withrespect to the processing chamber PC may be performed in parallel.

Further, a plurality of movable buffers 110 may be moved in parallelsuch that a plurality of substrates W may be moved independently fromeach other, or a movable buffer 110 may hold a plurality of substrates Wsuch that an unprocessed substrate W and a processed substrate W may bemoved at the same time.

Hereinafter, examples of the movable buffer 110 that holds thesubstrates W in multiple stages, and the transfer chamber 100 that usesthe multi-stage buffer 110 will be described using FIGS. 13A and 13B to15. First, the multi-stage movable buffer 110 will be described usingFIGS. 13A and 13B. FIG. 13A is a perspective view of the multi-stagemovable buffer 110. While a two-stage movable buffer 110 will bedescribed below, the number of stages may be three or more.

As illustrated in FIG. 13A, the movable buffer 110 includes the holdingmodule 111 and the driving module 112. The holding module 111 includes asupport 111 a, a bent portion 111 b, and holders 111 c 1 and 111 c 2.The support 111 a extends upward to support the bent portion 111 b atthe upper end thereof. The bent portion 111 b projects from the support111 a in the horizontal direction D1 (see, e.g., FIG. 1) which is themoving direction of the movable buffer 110.

Specifically, the bent portion 111 b includes a projecting portion 111 b1 that projects from the support 111 a along the horizontal direction D1such that the upper surface of the bent portion 111 b and the uppersurface of the support 111 a are flush with each other, and a supportcolumn 111 b 2 that is bent upward from the projecting portion 111 b 1.Further, the bent portion 111 b includes a folded-back portion 111 b 3that is bent from the support column 111 b 2 in the direction ofreturning to the support 111 a along the horizontal direction D1. Thetip end of the folded-back portion 111 b 3 does not project from thesupport column 111 a when viewed from above.

The holders 111 c 1 and 111 c 2 are members that hold the substrates W(see, e.g., FIG. 1), and are supported by the bent portion 111 b.Specifically, the holder 111 c 1 that corresponds to the first stage issupported by the upper surface of the support 111 a and the uppersurface of the projecting portion 111 b 1 of the bent portion 111 b. Theholder 111 c 2 that corresponds to the second stage is supported by theupper surface of the folded-back portion 111 b 3. The base ends of theholders 111 c 1 and 111 c 2 are supported by the bent portion 111 b, andthe tip ends thereof are each bifurcated. The space between the holders111 c 1 and 111 c 2 has a size enough to allow the entrance of the hand13 of the robot 10 (see, e.g., FIG. 4).

As described above, the holding module 111 illustrated in FIG. 13Aincludes the bent portion 111 b that is bent to prevent the interferencewith the substrate W placed on the first stage. Further, the bentportion 111 b has a cantilever shape opened at the side where thesupport column 111 b 2 is not provided (e.g., the side of the negativedirection of the X axis). Accordingly, even when the substrate W held bythe robot 10 (see, e.g., FIG. 4) is entering the bent portion 111 balong the Y axis, the movable buffer 110 may avoid the upward/downwardmovement operation of the robot 10. Specifically, the movable buffer 110may move toward the side where the support column 111 b 2 is provided(e.g., in the positive direction of the X axis), so as to avoid theupward/downward movement operation of the robot 10.

While FIG. 13A illustrates the movable buffer 110 in which the bentportion 111 b projects rightward (e.g., in the positive direction of theX axis) when viewed from the negative direction of the Y axis, the bentportion 111 b may project leftward (e.g., in the negative direction ofthe X axis). In this case, the avoiding operation described above may beperformed in the opposite direction (e.g., in the negative direction ofthe X axis).

The driving module 112 supports the holding module 111. The drivingmodule 112 has two concave portions 112 r that extend along thehorizontal direction D1, at the bottom surface thereof. The concaveportions 112 r correspond to two convex portions 120 r (see, e.g., FIG.13B) of the track 120 (see, e.g., FIG. 3) to be described later,respectively.

FIG. 13B is a perspective view of the movable buffer 110 and the track120. FIG. 13B illustrates the movable buffer 110 in a state of holdingthe substrates W. In FIG. 13B, the substrate W held by the holder 111 c1 that corresponds to the first stage is represented by a dashed line,and the substrate W held by the holder 111 c 2 that corresponds to thesecond stage is represented by a solid line.

As illustrated in FIG. 13B, it may be seen that the substrate W held bythe holder 111 c 1 reaches the entrance space of the bent portion 111 b.The track 120 has the two convex portions 120 r that extend along thehorizontal direction D1 at the upper surface thereof. The two convexportions 120 r correspond to the two concave portions 112 r (see, e.g.,FIG. 13A) of the driving module 112 described above, respectively.

Next, the transfer chamber 100 in which the movable buffer 110illustrated in FIGS. 13A and 13B is provided will be described usingFIGS. 14A and 14B. FIG. 14A is a schematic top view of the transferchamber 100, and FIG. 14B is a perspective top view of the transferchamber 100. FIGS. 14A and 14B omit the illustration of the processingchambers PC and the load lock chambers LL illustrated in FIG. 3 andothers, and instead, illustrate communication ports 101 provided in theside wall 100 sw of the transfer chamber 100 and configured tocommunicate with the processing chambers PC and the load lock chambersLL.

FIGS. 14A and 14B represent the four robots 10 provided in the transferchamber 100 as in FIG. 3, as robots 10-1, 10-2 . . . from the robotclosest to the load lock chambers LL, in order to discriminate the fourrobots 10 from each other. Further, FIGS. 14A and 14B represent theabove-described communication ports 101 as communication ports 101-1,101-2 . . . for the communication ports 101 provided in the side wall100 sw 1, and communication ports 101-5, 101-6 . . . for thecommunication ports provided in the side wall 100 sw 2.

Further, FIGS. 14A and 14B represent the movable buffer 110 providednear the side wall 100 sw 1 (see, e.g., FIG. 13A) as a movable buffer110-1, and the movable buffer 110 provided near the side wall 100 sw 2as a movable buffer 110-2. In the same manner, FIGS. 14A and 14Brepresent the track 120 as tracks 120-1 and 120-2. Since FIG. 14Brepresents the perspective view of the configuration illustrated in FIG.14A for facilitating the understanding of the configuration, thetransfer chamber 100 will be described below using FIG. 14A.

As illustrated in FIG. 14A, in the movable buffer 110-1, the bentportion 111 b (see, e.g., FIG. 13A) projects rightward (e.g., in thepositive direction of the X axis) when viewed from the robot 10, as inthe movable buffer 110 illustrated in FIG. 13A. Thus, the movable buffer110-1 moves rightward (e.g., in the positive direction of the X axis) soas to avoid the robot 10 in a posture in which the hand 13 holding thesubstrate W is brought close to the movable buffer 110. That is, asillustrated in FIG. 14A, when the movable buffer 110-1 is positioned infront of the communication port 101-1, the movable buffer 110-1 moves inthe positive direction of the X-axis so as to avoid the robot 10-1.

Accordingly, one end of the track 120-1 (e.g., in the negative directionof the X axis) is not required to extend toward the communication port101-9. In contrast, when the movable buffer 110-1 is positioned in frontof the communication port 101-4, the movable buffer 110-1 needs to avoidthe robot 10-4 in the positive direction of the X-axis, and hence, theother end of the track 120-1 (e.g., in the positive direction of the Xaxis) needs to be provided to extend in the positive direction of the Xaxis as illustrated in FIG. 14A.

Meanwhile, in the movable buffer 110-2, the bent portion 111 b (see,e.g., FIG. 13A) projects leftward when viewed from the robot 10, unlikethe movable buffer 110 illustrated in FIG. 13A. Thus, the movable buffer110-2 moves leftward so as to avoid the robot 10 in a posture in whichthe hand 13 holding the substrate W is brought close to the movablebuffer 110. The movable buffer 110-1 is provided to be symmetric withthe movable buffer 110-2 with respect to the line parallel to the Xaxis.

Thus, as illustrated in FIG. 14A, when the movable buffer 110-2 ispositioned in front of the communication port 101-5, the movable buffer110-2 may move in the positive direction of the X axis so as to avoidthe robot 10, similar to the movable buffer 110-1. Accordingly, one endof the track 120-2 (e.g., in the negative direction of the X axis) isnot required to extend toward the communication port 101-10. On thecontrary, when the movable buffer 110-2 is positioned in front of thecommunication port 101-8, the movable buffer 110-2 needs to avoid therobot 10-4 in the positive direction of the X axis, and hence, the otherend of the track 120-2 (e.g., in the positive direction of the X axis)needs to be provided to extend in the positive direction of the X axisas illustrated in FIG. 14A.

Next, an example of the operations of the robot 10 and the movablebuffer 110 illustrated in FIG. 14A will be described. It is assumed thata processed substrate W exists in the processing chamber PC (see, e.g.,FIG. 3) that communicates with the communication port 101-1, the robot10 is not holding a substrate W, an unprocessed substrate W is placed onthe second stage (e.g., the upper stage) of the movable buffer 110, andno substrate W exists on the first stage (e.g., the lower stage).

In this case, the movable buffer 110-1 stands by at a position deviatedfrom the robot 10-1 in the positive direction of the X axis relative tothe position illustrated in FIG. 14A, that is, in the vicinity of therobot 10-1. The robot 10-1 passes the hand 13 through the communicationport 101-1 to take the processed substrate W out of the processingchamber PC. Then, the robot 10-1 moves the hand 13 up or down whileretreating the hand 13, to the position where the substrate W may betransferred to the first stage of the movable buffer 110-1. The movablebuffer 110-1 moves from the standby position to the vicinity of therobot 10-1, and stops at the position where the hand 13 holding theprocessed substrate W enters between the first stage and the secondstage, in the X-axis direction.

The robot 10-1 moves the hand 13 forward. Then, the robot 10-1 moves thehand 13 down until the substrate W is placed on the first stage of themovable buffer 110-1. The movable buffer 110-1 that has received thesubstrate W moves away from the robot 10-1 again, and moves to thestandby position. The robot 10-1 retreats the hand 13 while moving thehand 13 upward to the height at which the hand 13 enters between thefirst stage and the second stage of the movable buffer 110-1. Themovable buffer 110-1 moves from the standby position to the vicinity ofthe robot 10-1, and stops at the position where the hand 13 that is notholding the substrate W enters between the first and second stages, inthe X-axis direction.

The robot 10-1 moves the hand 13 forward. Then, the robot 10-1 moves thehand 13 up until the hand 13 acquires the unprocessed substrate W placedon the second stage of the movable buffer 110-1. The movable buffer110-1 moves away from the robot 10-1 again, and moves to the standbyposition. Then, the robot 10-1 that has acquired the unprocessedsubstrate W moves the hand 13 forward, so as to carry the substrate Winto the processing chamber PC. In this way, the robot 10 and themovable buffer 110 operate in cooperation with each other, in order notto interfere with the substrates W or the like held by the robot 10 andthe movable buffer 110.

While FIG. 14A illustrates two tracks 120 (e.g., the tracks 120-1 and120-2), only either one track may be provided. For example, when onlythe track 120-1 is provided, each robot 10 transfers the substrate W incooperation with the movable buffer 110-1. For example, the robot 10-4accesses the processing chambers PC that communicate with thecommunication ports 101-4 and 101-8, respectively, in cooperation withthe movable buffer 110-1.

Next, a modification of the movable buffer 110 illustrated in FIG. 13Awill be described using FIG. 15. FIG. 15 is a view illustrating amodification of the multi-stage movable buffer 110. In the followingdescriptions, differences from the movable buffer 110 illustrated inFIG. 13A will be mainly described, and overlapping descriptions will beappropriately omitted.

The movable buffer 110 illustrated in FIG. 15 is different from themovable buffer 110 illustrated in FIG. 13A in that the bent portion 111b is bent in a different direction from that in the movable buffer 110of FIG. 13A. As illustrated in FIG. 15, in the bent portion 111 b, theprojecting portion 111 b 1 projects from the support 111 a in thepositive direction of the Y axis such that the upper surface of theprojecting portion 111 b 1 and the upper surface of the support 111 aare flush with each other. The support column 111 b 2 bent upward fromthe projecting portion 111 b 1 is positioned on the side of the positivedirection of the Y axis. Further, the folded-back portion 111 b 3 isbent in the negative direction of the Y axis.

When the movable buffer 110 illustrated in FIG. 15 is used in place ofthe movable buffer 110 illustrated in FIG. 13A, the support column 111 b2 does not cause any interference, so that the movable buffer 110 mayavoid the robot 10 or the substrate W by moving in any side of thehorizontal direction D1. Accordingly, the other end of the track 120illustrated in FIG. 14A (e.g., in the positive direction of the X axis)may not be provided to extend in the positive direction of the X axis asillustrated in FIG. 14A. Thus, the entire length of the track 120 may bereduced, so that the volume of the transfer chamber 100 may be reduced.

Further, when the movable buffer 110 illustrated in FIG. 15 is used, thewidth of the transfer chamber 100 (e.g., the width along the Y axis) islarger than that when the movable buffer 110 illustrated in FIG. 13A isused. Accordingly, when it is desired to reduce the width of thetransfer chamber 100, the movable buffer 110 illustrated in FIG. 13A maybe used.

As described above, the transfer system 1 according to the embodimentincludes the transfer chamber 100 in which the plurality of processingchambers PC are provided on the side wall 100 sw to each perform aprocessing on the substrate W in a decompressed atmosphere, and thesubstrate W is transferred under the decompressed atmosphere. Thetransfer chamber 100 includes the plurality of robots 10 fixed in thetransfer chamber 100 and configured to each transfer the substrate W,and the movable buffer 110. The movable buffer 110 holds the substrateW, and moves in the horizontal direction along the side wall 100 swbetween the side wall 100 sw and the robots 10. Each robot 10 transfersthe substrate W between the movable buffer 110 and a processing chamberPC in cooperation with the movement of the movable buffer 110.

In the transfer system, the robot is fixed, and the buffer where thesubstrate is placed is movable, such that the substrate is transferredby the cooperate operation of the robot and the movable buffer, and as aresult, the weight of the moving subject may be reduced. Accordingly,the moving mechanism may be simplified, and the operating rate of themoving mechanism may be improved, so that the availability for thetransfer of the substrate may be improved. Accordingly, it becomespossible to improve the transfer efficiency of the substrate.

According to an aspect of an embodiment, it is possible to provide atransfer system, a transfer method, and a transfer apparatus which arecapable of improving the transfer efficiency of a substrate.

From the foregoing, it will be appreciated that various embodiments ofthe present disclosure have been described herein for purposes ofillustration, and that various modifications may be made withoutdeparting from the scope and spirit of the present disclosure.Accordingly, the various embodiments disclosed herein are not intendedto be limiting, with the true scope and spirit being indicated by thefollowing claims.

What is claimed is:
 1. A transfer system comprising: a transfer chamberhaving a side wall provided thereon with a plurality of processingchambers in which a processing is performed on a substrate under adecompressed atmosphere, and configured such that the substrate istransferred under the decompressed atmosphere; a plurality of robotsfixed in the transfer chamber and configured to transfer the substrate;and a movable buffer configured to hold the substrate, and move in ahorizontal direction along the side wall between the side wall and therobots in the transfer chamber, wherein the robots exchange thesubstrate between the movable buffer and the processing chambers incooperation with a movement of the movable buffer.
 2. The transfersystem according to claim 1, wherein a load lock chamber is provided onthe side wall of the transfer chamber, and an internal pressure of theload lock chamber is changed between the decompressed atmosphere and anatmospheric-pressure atmosphere, and at least one of the plurality ofrobots exchanges the substrate between the movable buffer and theprocessing chambers or the load lock chamber.
 3. The transfer systemaccording to claim 1, wherein the movable buffer is configured to beable to stop in front of the side wall when viewed from the robots. 4.The transfer system according to claim 1, wherein the transfer chamberincludes a track fixed therein, the movable buffer includes a holdingmodule configured to hold the substrate, and a driving module thatcorresponds to a mover of a linear motor, and the driving module isdriven in a non-contact manner by a stator included in the track.
 5. Thetransfer system according to claim 4, wherein the holding moduleincludes a holder configured to hold the substrate in two upper andlower stages.
 6. The transfer system according to claim 4, wherein theside wall is linear when viewed from above, and is provided thereon withthe plurality of processing chambers arranged in the horizontaldirection, the plurality of robots are provided along an arrangementdirection of the processing chambers, and the track is fixed at aposition close to the side wall relative to the robots, and is a lineartrack along the arrangement direction.
 7. The transfer system accordingto claim 6, wherein the linear track includes a curved portion that iscurved in a direction away from the side wall, at either one of bothends thereof.
 8. The transfer system according to claim 6, wherein thetransfer chamber has a rectangular shape when viewed from above, andincludes a first side wall and a second side wall that correspond torelatively long sides of the rectangular shape, a first linear trackthat is the linear track provided between the first side wall and therobots, and a second linear track that is the linear track providedbetween the second side wall and the robots.
 9. The transfer systemaccording to claim 8, wherein the transfer chamber includes a firstcurved track that connects one-side ends of the first linear track andthe second linear track to each other.
 10. The transfer system accordingto claim 9, wherein the transfer chamber includes a second curved trackthat connects the other-side ends of the first linear track and thesecond linear track to each other.
 11. The transfer system according toclaim 4, wherein a plurality of movable buffers is provided for onetrack, and is movable independently from each other.
 12. The transfersystem according to claim 4, wherein a plurality of movable buffers isprovided for one track, and is connected to each other.
 13. The transfersystem according to claim 4, wherein the movable buffer includes twoholding modules and one driving module, and the holding modules areconnected to both ends of the driving module in the horizontaldirection, respectively.
 14. The transfer system according to claim 1,wherein the plurality of robots include a first robot with three degreesof freedom which include one degree of freedom in a vertical directionand two degrees of freedom in the horizontal direction, and the firstrobot is disposed in front of one of the processing chambers.
 15. Thetransfer system according to claim 2, wherein the plurality of robotsinclude a second robot with four or more degrees of freedom whichinclude one degree of freedom in the vertical direction and three ormore degrees of freedom in the horizontal direction, and the secondrobot access the load lock chamber and one of the processing chambers,or access the plurality of adjacent processing chambers on the sidewall.
 16. The transfer system according to claim 2, wherein theplurality of robots include a third robot provided with a dual arm thateach has two degrees of freedom in the horizontal direction, and havingone degree of freedom in the vertical direction, and the third robot isdisposed at a position closest to the load lock chamber, among theplurality of robots.
 17. The transfer system according to claim 1,wherein the plurality of robots includes a fourth robot with two degreesof freedom in the horizontal direction, and the movable buffer includesa lifter configured to move the substrate up and down.
 18. The transfersystem according to claim 1, wherein the plurality of robots include afifth robot with two degrees of freedom which include one degree offreedom in the vertical direction and one degree of freedom in thehorizontal direction, and the fifth robot is provided with a hand inwhich two forks each configured to hold the substrate are connected backto back, and is disposed in front of one of the processing chambers. 19.A transfer method comprising: providing a transfer system including atransfer chamber having a side wall provided thereon with a plurality ofprocessing chambers in which a processing is performed on a substrateunder a decompressed atmosphere, and configured such that the substrateis transferred under the decompressed atmosphere, a plurality of robotsfixed in the transfer chamber and configured to transfer the substrate,and a movable buffer configured to hold the substrate, and move in ahorizontal direction along the side wall between the side wall and therobots in the transfer chamber; and operating the robots and the movablebuffer in cooperation with each other, to exchange the substrate betweenthe movable buffer and the processing chambers.
 20. A transfer apparatuscomprising: a plurality of robots fixed in a transfer chamber andconfigured to transfer a substrate, the transfer chamber having a sidewall provided thereon with a plurality of processing chambers in which aprocessing is performed on the substrate under a decompressedatmosphere, and configured such that the substrate is transferred underthe decompressed atmosphere; a movable buffer configured to hold thesubstrate, and move in a horizontal direction along the side wallbetween the side wall and the robots in the transfer chamber; and acontroller configured to operate the robots and the movable buffer incooperation with each other, to exchange the substrate between themovable buffer and the processing chambers.